sludge

/slʌdʒ/ (bre, ipa) · /slʌdʒ/ (ame, ipa) · /ˈsləj/ (ame, mw)

sludge — noun

1. thick, soft, wet earth or a similar semi-liquid substance that is messy and hard

1.名詞B2
釋義

thick, soft, wet earth or a similar semi-liquid substance that is messy and hard to clean up, often found after rain or flooding.

例句

After three days of heavy rain, the hiking trail was completely covered in thick brown sludge.

uncountable: covered in + thick brown sludge

The workers had to shovel the foul-smelling sludge out of the drainage ditch before the next storm arrived.

collocation: shovel sludge / drainage ditch sludge

同義詞
  • mud

    general term for wet earth; sludge is thicker and more unpleasant

  • muck

    informal; emphasises dirtiness and mess

  • ooze

    thick, slow-moving liquid mud, often at the bottom of a body of water

  • silt

    fine sand or soil carried by water; grainier and less viscous than sludge

文法句型

sludge from [source]

a layer/pool of sludge

用法筆記

Uncountable noun — never used as 'a sludge' or 'sludges'. Often paired with the source of the sludge (river sludge, flood sludge) or a descriptor of its consistency (thick sludge, greasy sludge).

常見錯誤

❌The rain left sludges on the path.
✅The rain left sludge on the path.
💡Sludge is uncountable and has no plural form.
❌I stepped in a sludge.
✅I stepped in some sludge.
💡Use 'some' or 'a pool/patch/layer of' instead of the indefinite article.

2. the thick, semi-solid waste material that is left after water and waste have bee

2.名詞C1
釋義

the thick, semi-solid waste material that is left after water and waste have been treated in a factory or sewage plant, and which may be processed further or disposed of.

例句

The water treatment plant dries the sewage sludge and sells it to farmers as fertiliser.

collocation: sewage sludge / treatment plant sludge

New regulations require all factories to dispose of chemical sludge at licensed waste facilities.

collocation: chemical sludge / dispose of sludge

同義詞
  • waste

    broader term for any unwanted material; sludge is a specific semi-solid type

  • sediment

    solid particles that settle at the bottom of a liquid; less specific to waste processing

  • residue

    what remains after a process; can be solid or liquid

文法句型

sewage/industrial/chemical sludge

sludge from [plant/process]

用法筆記

Common in environmental engineering and waste-management contexts. Often modified by its source: sewage sludge, industrial sludge, chemical sludge. Uncountable; the plural 'sludges' is sometimes used in technical writing to refer to different types, but learners should treat it as uncountable.

常見錯誤

❌The factory produces a sludge.
✅The factory produces sludge.
💡Sludge is uncountable; avoid the indefinite article.
❌Sewage sludges are harmful.
✅Sewage sludge is harmful.
💡Treat as uncountable unless you are in a technical context discussing different types.